Chemo Brain: What it is and How to Manage it

What is Chemo Brain? 

Every year in the United States, over a million people receive chemotherapy or radiation treatment for cancer.  While many chemotherapy drugs can have a powerful effect on longevity and surviving cancer, they destroy both cancer cells and healthy cells, leading to a number of side effects.1   

One of these is known as ‘chemo brain’ (or ‘chemobrain’), a form of debilitating cognitive impairment that sometimes follows cancer treatment.  Sufferers complain of ‘chemo brain fog’, describing a period of fatigue, poor memory, and other signs of cancer-related cognitive change.  The symptoms can improve quickly, but some people experience months or years of decreased mental sharpness.2 

What Are the Symptoms of Chemo Brain? 

Patients struggling with post-chemotherapy cognitive impairment report problems with the following:  

  • memory and recall,  
  • difficulties multi-tasking,  
  • persistent fatigue and poor sleep, and  
  • reduced concentration and attentiveness.3  

    Words come more slowly to mind, tasks take longer to complete, and new skills are learned less readily.4  Some people find they become self-conscious about their sluggish mental skills, leading to isolation and depression, which could in turn lead to even further worsening of cognitive abilities and functions.5 

    What Causes Chemo Brain? 

    Chemotherapy-induced cognitive impairment seems to resemble accelerated brain aging in many respects.  Chemotherapeutic drugs are toxic to the central nervous system, causing a dangerous imbalance between oxygen-containing molecules and free radicals, a family of unstable molecules which can cause cell damage.  When these two are misaligned, the result is oxidative stress, a major contributor to aging of the brain and body.6  There’s also a complex relationship between cancer, its treatment, and the patient’s immune system.  Chemotherapy can trigger a stress response in the body due to the secretion of inflammatory chemicals from affected cells.  Systemic inflammation like this can cause joint and muscle pain, sleep disorders, and weight gain or loss, which helps explain why chemo patients feel so terrible after their treatments.7  Chemo drugs can also literally shrink the hippocampus, an area of the brain which is crucial for memory, spatial navigation, and cognitive flexibility.8  

    Of course, the toxicity of chemo drugs extends to the entire body. Some breast cancer treatments can cause very significant damage.  Doxorubicin, known as ‘The Red Devil,’ owing to its red color, can cause dangerous heart problems.9  Cisplatin can lower a patient’s white blood cell count, increasing the risk of infection.10  It also seems to increase levels of a signaling molecule called sphingosine-1-phosphate (S1P), which is normally helpful, but excessive amounts are linked to memory problems and underlying mitochondrial dysfunction and inflammation.11 

    How Long Do Chemo Brain Fog Symptoms Last? 

    As many as 75% of cancer patients experience aspects of chemo brain.12  Most symptoms improve after 9-12 months, but a substantial portion (10-20%) of chemotherapy patients experience longer-term symptoms, and some still report effects after as long as 10 years or more.13  


    How Can You Reduce the Symptoms of Chemo Brain? 

    There is no existing drug to treat chemo brain.  Instead, patients are encouraged to follow a suite of behavioral and nutritional guidelines before, during, and after cancer treatment.  Exercise is a key element, and physical activity before and after chemo treatment has shown benefits.14  Cancer treatments can disrupt sleep, which is essential for a healthy brain, so experts recommend relaxation therapy and good sleep hygiene.15, 16  Not surprisingly, brain games and puzzles can help with the cognitive effects of chemo brain, while meditation and other mindfulness-based interventions have shown positive outcomes.17, 18  Interestingly, neurofeedback (where patients observe real-time data from their own brain) also shows promise.19 

    Nutrition and Chemo Brain 

    Diet can play a key role in addressing cancer-related cognitive impairment..20  Studies have shown that increasing the consumption of vegetables, fruit, fish, and green tea reduces cognitive impairment in cancer survivors.21  The Dietary Approach to Stop Hypertension (DASH) diet, and other diets based on the Mediterranean diet, such as the MIND diet, are good candidates for treating chemo brain.  These diets emphasize fresh fruit and vegetables, more monounsaturated fats (found in nuts, avocado, and olive oils) and less saturated fats (such as those in butter, cheese, and fatty meats).22  A diet rich in omega-3 oils (found in cold water fatty fish, chia seeds, and walnuts) but low in added sugar (high sources being candy, sodas, and pastries) was found to protect breast cancer survivors against the oxidative stress and inflammation associated with chemo brain.23  

    Dietary responses to chemo brain must address the common nutrient deficiencies experienced by chemotherapy patients: vitamin D (eggs, fortified milk, tuna), vitamin B12 (fish, eggs, poultry), magnesium (spinach, avocados, bananas) and omega-3 oils (walnuts, salmon, sardines).  Meals which emphasize antioxidant-rich foods (pecans, berries, kale, etc.) are recommended, and experts have consistently promoted the neuroprotective compounds found in green tea: flavonols and catechins.24  

    Another strategy to support brain health during cancer recovery is to use nutritional supplementation to close nutritional gaps.  Our nutritional supplement called RELEVATE by NeuroReserve is one option to consider.  RELEVATE contains 17 well-researched nutrients to support long-term brain health.  The dosages of RELEVATE’s ingredients are based on those consumed in brain-healthy, ‘neuroprotective’ diets like the Mediterranean and MIND diets, and are derived from long-term medical studies of these brain-strengthening diets.  This research makes RELEVATE both a natural resource for chemo brain and an excellent overall nutritional choice for cancer survivors.  Two-thirds of RELEVATE users report that they feel sharper or have improved clarity and less brain fog.25  You can learn more about these powerful nutrients here

    The Future of Chemo Brain 

    It’s very likely that new research will show that the most successful responses to chemotherapy brain fog are multi-domain therapies: a combination of nutrition, exercise, sleep, and cognitive training.  Toxic chemotherapy drugs can injure the brain much like the aging process, but at an accelerated rate.  With no simple solution on the horizon, cancer patients must continue to depend on wise lifestyle choices to survive and thrive with a vibrant and healthy mind.  

    If you’re interested in more evidence-based articles, brain health tips, recipes and more, sign up for our newsletter here. 


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    25.  Survey conducted by NeuroReserve in March 2022. 
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